The market for automated pharmacy equipment is increasingly in need of a device that reliably, cost-efficiently, and rapidly automates the process of filling a prescription with minimal risk of contamination. This industry extends to both the retail and hospital markets.
Pricing pressures and shrinking margins have forced retail pharmacies to rely more on technological solutions to improve process efficiency, performance, and cost. The number of annual prescriptions continues to grow while a shortage of pharmacists remains. Consequently, the number of pharmacists in the workforce has fallen behind the increase in prescription demand.
Also, the increasing pressure from consumers to lower drug prices and fixed costs from pharmaceutical suppliers has led to decreasing margins. This trend is projected only to worsen in the future.
Further, professional skills in the hospital segment should be directed to primary care rather than pill-counting and a great need exists to replace obsolete technology to fill individual and outpatient prescriptions. Currently, both hospitals and nursing homes use products called “nursing stations,” which generally contain a smaller version of the pharmacy contained within the institution. However, these products are cumbersome and outdated.
With regard to dispensing medication in the hospital and nursing home segment, prescriptions are dispensed in single doses. This market is in great need of convenience, security, and inventory control. Currently, hospitals use centralized pharmacies to prepare and dispense medications, which requires advance notice and sometimes results in delivery errors. Additionally, many hospitals store commonly dispensed medications in locked cabinets on a specified floor where they are commonly administered by nurses or doctors who retrieve the prescription in individual doses and administer it to the patient. A main issue with the nursing station units is that more than one dose is accessible at a time, which can lead to the problem of pill theft. To avoid this problem, many pharmacies monitor each unit on-line on a daily basis. This manages inventory and also prevents abuse. However, an automated pill counting design would result in a dramatic improvement in inventory control, efficiency and cost by eliminating overhead and the amount of time individuals must spend performing the steps currently involved in pill dispensation.
With regard to drugstores and other places where pharmaceuticals are sold, industry trends in prescription growth, store construction, and workforce shortages predict that stores without automated systems will face intense competition in terms of price and service from stores with more cost-efficient means of delivering prescriptions to their customers. Thus, a way to cut operational costs while maintaining a high level of customer service with a shortage of pharmacists and increasing prescription demand is to use technology to automate the prescription filling process.
Presently, a high-throughput approach to pill dispensation has involved the two steps of fluidization and singulation to extract individual pills from a bin. Additionally, this approach operates on a “per-bin” basis where individual bins contain every necessary subsystem component. Fluidization involves agitating, and at times levitating the pills to randomize their position and orientation. Fluidization must be continuously applied to ensure that pills have opportunities to match the singulation mechanism. Fluidization may be induced mechanically or pneumatically. Singulation involves extracting or ejecting individual pills from the fluidized bin. This generally requires an individual pill to assume a specific position at a particular point in space so that it can be aligned with the mechanism channel or port.
Many automated systems that utilize fluidization and singulation exist today in the marketplace. The McKesson Robot Rx is an automated system that uses Baker Cells, a robot retrieval arm, and a central dispensing interface. The pills are stored within the Baker Cell units and singulation extracts individual pills in a channel, through centrifugal force. A variation of this design is used in hospitals to load individual doses into plastic bags for daily administration. However, this process is slow due to the time required to retrieve each cell. Also, the equipment requires a large amount of floor space.
A design by Parata fluidizes and singulates pills using high pressure air, air ejectors, and solenoid control valves. A centralized vacuum circulates pills in the hopper while outbound jets use air flow to extract individual pills and drive them through a nozzle or spout. A separate pneumatic jet is used to redirect overcounts of pills back into the bin. Each bin contains a microprocessor, multiple solenoids, counting sensors, actuators, and a connection for network communications. These control components occupy a large volume of bin space, reducing the volume available for pills. A minimum number of pills are needed to support fluidization.
The known art includes attempts to use a vacuum source to attract pills and a torque source to rotationally transport pills for counting and dispensing purposes. Regarding this feature, two designs are noteworthy.
One design uses a vacuum drum pill counter used to count and dispense pills or tablets using a vacuum source. The device includes a counter housing containing a vacuum drum which includes a front wall, a rear wall and a perimeter wall. The front wall contains a plurality of pill apertures for attracting pills to the exterior front wall of the drum through a vacuum source that draws a vacuum through the inside of the drum to hold the pills in place. A torque source connected to the vacuum drum is used to rotate the vacuum drum. A pill separator removes pills attached to the pill apertures onto a pill shelf and a sensor attached to the housing detects the removal of the pills. A pill feeder is attached to the housing to regulate the amount of pills which come into contact with the drum. This prevents a large volume of pills from piling on the apertures of the drum and affecting the consistent retention of pills on the pill apertures.
Several disadvantages are associated with this design, namely, the placement of pill apertures on the exterior of the rotating drum requires that the vacuum source be strong enough to attract pills to the apertures and overcome the centrifugal force caused by rotation of the drum. Thus, as the drum increases speed to pick up pills more quickly, the centrifugal force works against the vacuum force. As a result, the vacuum force must be increased as well, requiring more power. Further, the use of an external pill feeder to regulate the amount of pills that come into contact with the pill apertures discourages the maximum possible number of pills from being collected and results in decreased efficiency.
Another design uses a flat disk with pill apertures located on the exterior flat surface. A vacuum drive wheel and vacuum source are applied to attract pills resting against the disk to the apertures. The disk rotates and carries the pills until they are separated one at a time by a separator wall. A photoelectric cell at the discharge opening counts each pill and a continuously feeding pill cassette positions pills against the flat disk. An agitator consisting of radial spokes turns with the conveying wheel to break up pills and prevent them from bridging together.
This design also attracts pills to the exterior flat surface of a solid flat disk, and thus, suffers from the same disadvantages in configuration, as previously discussed. This configuration works against centrifugal force, making it necessary to increase the power of the vacuum force in order to attract the pills. Further, this system relies on an agitator to cause fluidization of the pills using a series of spokes. This however, may cause the pills to chip, break or become damaged, in addition to creating large amounts of dust leading to cross-contamination.
Many known automated dispensing systems utilize several complex system components including a counter, a type of control circuitry, sensor, motor source, and chute or slide for dispensation. A disadvantage of these systems is that each bin is comprised of dedicated subsystems for dispensing, counting and controlling. This results in redundancy (e.g., high manufacturing and maintenance costs to replicate several bins) and a higher chance of leakage.
Thus, there is a clear need for an efficient vacuum pill collector and dispenser system that works with centrifugal force to attract and hold pills, maximizes the opportunity for pill capture, maximizes efficient usage of space, eliminates the need for fluidization or an agitator, and eliminates redundancy to reduce maintenance and manufacturing costs. There is a clear need for a pill collection and dispensing device that reduces the complexity of the collection and dispensation process, costs less than current systems, is reliable, fast, requires little maintenance, and has low contamination risk. The present invention is such a system.
The system of the present invention provides an effective method of pill collection, sorting, counting, and dispensing using a vacuum source, a rotating transport substrate, and a unique end-effector design for cost and space savings. An automated system such as the present invention can remedy many of the problems associated with manual and currently-known automatic pill dispensation. For example, it can increase counting accuracy, lower costs, expand the pharmacy's or hospital's capabilities, increase total pill volume, increase volume per bin, increase reliability and increase filling speed. The system is also easy to operate, can be integrated with other necessary systems, and has a low maintenance cost.
In short, the system of the present invention proposes a new approach to pharmacy automation, which allows a degree of scalability and modularity such that it meets the needs of customers in terms of size, cost and function. By utilizing fewer and simpler parts, the system is more cost-efficient, more compact, and more reliable.